Background:Nationwide epidemiological studies of cardiac implantable electronic devices (CIEDs) encompassing multiple device types and strategies remain limited in Japan, particularly regarding epicardial lead use and pediatric populations. Methods:We performed the first nationwide analysis of CIED implantation trends using the National Database of Health Insurance Claims, including transvenous (TV)/epicardial (Epi) systems for pacemakers, implantable cardioverter-defibrillators (ICDs), cardiac resynchronization therapy (CRT), and CRT-defibrillators (CRTDs), as well as leadless pacemakers, subcutaneous ICDs (S-ICDs), and epicardial lead use. Epicardial lead and pediatric characteristics were supplemented using industry data. Results:In fiscal year 2023, implantation rates per 100 000 population were 29.69 for TV-pacemakers, 7.06 for leadless pacemakers, 2.42 for TV-ICDs, 0.889 for S-ICDs, 1.20 for TV-CRT, and 1.69 for TV-CRTDs. Rates for epicardial systems were lower, at 0.173 for Epi-pacemakers, 0-0.007 for Epi-ICDs, 0.024 for Epi-CRT, and 0.027 for Epi-CRTDs, while epicardial lead use was 0.545. S-ICD use increased across age groups, whereas TV-ICD implantation declined (all p < 0.001). Implantation of TV and leadless pacemakers, TV-CRT, and TV-CRTDs increased over time (all p < 0.001). Epicardial lead use showed a bimodal age distribution, peaking in pediatric and elderly populations, and declined in older adults while remaining stable in children and adults aged 20-49 years (p < 0.001). Pediatric CIED volumes were low, with several ICD, CRT, and CRTD procedures annually. Conclusions:CIED strategies in Japan demonstrate age-dependent variation. Epicardial systems remain indispensable in pediatric and congenital heart disease care, whereas alternative technologies are increasingly adopted in older adult populations, reflecting evolving lifespan-related device strategies.
Remote monitoring (RM) has been established as a standard tool for the management of patients with cardiac implantable electronic devices (CIEDs), offering advantages such as early event detection, fewer routine outpatient visits, and reduced mortality. As RM becomes more common, its appropriate implementation and the need for safe, efficient management have become increasingly important. This statement of the Japanese Heart Rhythm Society (JHRS) provides comprehensive guidance for medical professionals and device manufacturers involved in RM. Specifically, it outlines recommendations on personnel placement, workflow optimization, patient and caregiver education, alert notification settings, physiological parameter monitoring, and insurance claims. It also addresses the responsibilities of device manufacturers, the use of third-party resources, and strategies for reducing workload based on alert notifications. Recommendation classes and evidence levels were determined by the consensus of the writing team, and the proposed recommendations were reviewed and peer-reviewed by the JHRS' Committee on Implantable Devices.
This study investigated the hemolysis risk, renal, and safety outcomes between two pulsed field ablation (PFA) systems. A systematic review and meta-analysis were performed using PubMed, Cochrane, and ScienceDirect databases for all studies comparing circular to pentaspline PFA systems. Pooled markers evaluated included procedural characteristics, haptoglobin, lactate dehydrogenase (LDH), bilirubin, hemoglobin, and creatinine, with glomerular filtration rate (GFR) and safety markers qualitatively discussed. A total of 11 studies were included, comprising 1517 individuals. While differences in procedural, left atrial dwelling, and fluoroscopy times were statistically insignificant between the two PFA systems, the pentaspline system was significantly associated with lower post-procedural haptoglobin levels (SMD: 0.59; 95% CI: 0.25 to 0.93), higher LDH (SMD: -0.87; 95% CI: -1.49 to -0.253), and higher bilirubin levels (SMD: -0.77; 95% CI: -1.13 to -0.42) compared to circular catheters. No significant differences were observed in total hemoglobin levels (SMD: 0.13; 95% CI: -0.17 to 0.44; p = 0.206) or the magnitude of creatinine change (SMD: -0.02; 95% CI: -0.07 to 0.030; p = 0.270) between the systems. However, the incidence of acute kidney injury (AKI) was more pronounced in the pentaspline cohort with five documented cases, and more peri/post-procedural complications were recorded for the pentaspline system than for circular catheters. Pentaspline systems were associated with more pronounced laboratory markers of hemolysis, although clinically significant renal dysfunction remained uncommon and evidence regarding clinical consequences remains limited. Future studies are encouraged to standardize both reporting and data collection procedures to facilitate direct comparisons and tests of validity.
ABSTRACT Aims Pulsed field ablation (PFA) is a non‐thermal alternative to conventional thermal ablation for paroxysmal atrial fibrillation (AF). We conducted an updated systematic review and meta‐analysis of randomized evidence comparing efficacy, safety, and procedural outcomes. Methods PubMed/MEDLINE and the Cochrane Central Register of Controlled Trials were searched from inception through March 2026 for randomized controlled trials (RCTs) comparing PFA with thermal ablation in adults undergoing first catheter ablation for paroxysmal AF. Risk ratios (RRs) or mean differences (MDs) with 95% confidence intervals (CIs) were pooled using random‐effects models. Results Four RCTs enrolling 1 393 patients were included. PFA showed no statistically detectable difference in 12‐month treatment success (RR, 1.04; 95% CI, 0.97 to 1.12; I 2 = 7%), recurrent atrial arrhythmias (RR, 1.00; 95% CI, 0.77 to 1.29; I 2 = 42%), or composite serious adverse events (RR, 0.71; 95% CI, 0.32 to 1.57; I 2 = 7%). PFA shortened procedure time (MD, −22.42 min; 95% CI, −33.44 to −11.39; I 2 = 91%) and LA dwell time (MD, −25.73 min; 95% CI, −34.66 to −16.79; I 2 = 92%), but increased fluoroscopy time (MD, 7.34 min; 95% CI, 0.39 to 14.30; I 2 = 98%). Conclusions Across the included trial configurations, 12‐month efficacy estimates did not differ detectably. Sparse safety events and wide confidence intervals precluded equivalence claims. Pooled procedure and LA dwell times favored PFA, but platform, comparator, and workflow heterogeneity limit generalizability. Procedural findings are exploratory and should not be interpreted as direct energy‐specific effects.
ABSTRACT Background Anemia is common in patients with atrial fibrillation (AF). Prior studies have associated anemia—based on a single pre‐procedural hemoglobin measurement—with AF recurrence after catheter ablation. However, it remains unclear whether chronic anemia confers a different risk compared with transient anemia. This study evaluated the association between transient and chronic anemia and AF recurrence following first‐time catheter ablation. Methods In this nationwide cohort study, we included 15 017 patients from the Danish National Ablation Database undergoing first‐time AF ablation between 2010 and 2024 with available hemoglobin measurements within 12 months prior to the procedure. Patients were categorized as having no anemia, transient anemia, or chronic anemia based on repeated hemoglobin measurements. The primary outcome was AF recurrence within 1 year after a 90‐day blanking period, defined as a composite of AF‐related hospitalization, cardioversion, antiarrhythmic drug use, or repeat ablation. Associations were assessed using multivariable Cox proportional hazards models. Results A total of 877 patients (5.8%) had chronic anemia and 1592 (10.6%) had transient anemia. During follow‐up, 3445 patients (23.6%) experienced AF recurrence. The 1‐year cumulative incidence of recurrence was highest in patients with chronic anemia (32.5%), followed by transient anemia (24.2%) and no anemia (23.0%). Compared with non‐anemic patients, chronic anemia was independently associated with an increased risk of AF recurrence (adjusted hazard ratio [HR]: 1.36; 95% confidence interval [CI]: 1.18–1.56), whereas transient anemia was not (HR: 0.98; 95% CI: 0.87–1.10). Conclusion Chronic—but not transient—anemia prior to first‐time catheter ablation was independently associated with a higher risk of AF recurrence.
An automated external defibrillator (AED) captured the real-time transition from pre-excited atrial fibrillation to ventricular fibrillation in a previously undiagnosed patient with WPW syndrome. This case highlights the malignant potential of rapidly conducting accessory pathways.
ABSTRACT Background VASCADE MVP device has garnered attention as a novel femoral venous closure device. Manual compression (MC) is associated with prolonged bed rest and significant patient discomfort. Although Perclose ProGride/ProStyle device reduces bed rest duration, it can result in severe puncture site complications. The adoption of VASCADE MVP is anticipated to reduce the incidence of puncture site complications and facilitate early patient mobilization. Methods A total of 858 patients undergoing catheter ablation were included in this study (MC: n = 196; Perclose: n = 547; VASCADE: n = 115). Perclose device was introduced in January 2018, and VASCADE device in September 2024. Venous closure devices were employed for all suitable femoral puncture sheaths. In the MC group, compression was released after 7 h or the following morning; in the Perclose group after 4 h and in the VASCADE group after three or 4 h. Total post‐procedure time and vascular complications were compared among the groups. Results The total post‐procedure time was significantly shorter with VASCADE compared to Perclose and MC (22.6 ± 8.9 min vs. 29.6 ± 8.2 min and 30.4 ± 9.3 min, p < 0.001). The incidence of re‐bleeding was comparable between Perclose and VASCADE (11% vs. 13%, p = 0.787). No serious complications were observed in VASCADE group, whereas three patients (1%) in Perclose group experienced major complications. Conclusion The use of VASCADE devices safely reduced both total post‐procedure time and bedrest times for complete hemostasis, without an associated increase in complications.
Background:Atrial fibrillation (AF) is prevalent in cardiac amyloidosis (CA) and is associated with adverse clinical outcomes. Catheter ablation is increasingly used for rhythm control in this population, yet its clinical outcomes remain uncertain. We performed a systematic review and meta-analysis to evaluate arrhythmia recurrence and clinical outcomes following catheter ablation compared with medical therapy in patients with CA. Methods:We systematically searched MEDLINE, Embase, and Scopus from inception through December 2025 for studies evaluating catheter ablation of atrial arrhythmias in CA. Cohort studies reporting arrhythmia recurrence and/or clinical outcomes were included. The primary outcome was freedom from atrial arrhythmia (AA) following ablation. Secondary outcomes included all-cause mortality, heart failure hospitalization, and stroke. Random-effects models were used to pool event rates and odds ratios (ORs). Results:Thirteen observational studies comprising 797 patients with CA and AF were included. The pooled rate of freedom from AA following catheter ablation was approximately 50% (95% CI 37%-63%; I2 = 71.7%). The all-cause mortality analysis included 4 observational studies comprising 616 patients. Catheter ablation was associated with lower odds of all-cause mortality (OR 0.26, 95% CI 0.11-0.60; I2 = 18.4%); however, this association should be interpreted with caution given the retrospective design and risk of bias. No statistically significant differences were observed for heart failure hospitalization or stroke. Conclusions:In patients with CA, catheter ablation was associated with modest arrhythmia-free survival and lower odds of all-cause mortality. However, all contributing studies were observational cohorts. Randomized studies are needed to confirm these findings.
Background:Patients with heart failure (HF) can be monitored remotely using cardiovascular implantable electronic devices (CIEDs). In Japan, the HeartInsight algorithm has been implemented in selected implantable cardioverter defibrillators and cardiac resynchronization therapy devices. This retrospective study investigated whether elevations above, and daily fluctuations in, the HeartInsight score threshold aid prediction of hospitalization for HF. Methods:This study included 61 patients. Data were extracted from the BIOTRONIK Home Monitoring system; the number of days of HeartInsight score calculation, coefficient of variation, standard deviation, maximum value during the observation period, and mean values were analyzed. The primary endpoint was the first hospitalization for HF after CIED implantation. Patients were divided into two groups (HF hospitalization and non-HF hospitalization), and each parameter was compared between the groups. Results:The first hospitalization for HF after CIED implantation occurred in 10 of 61 patients (16%). Although the HF hospitalization group was younger than the non-HF hospitalization group, the two groups exhibited no differences in coronary risk factors, pharmacological therapies, or threshold elevation in HeartInsight scores. However, the HF hospitalization group demonstrated a tendency toward higher values, with significant differences observed in the maximum value and the difference between the maximum and mean values. Although few patients exhibited threshold elevation, greater daily variability was associated with a higher tendency toward HF hospitalization. Conclusions:Although predicting HF hospitalization based solely on threshold elevation is challenging, monitoring daily fluctuations may aid prediction. Evaluating score variability is important, even among patients without threshold elevation.
ABSTRACT Background Cardiac resynchronization therapy (CRT) improves outcomes in patients with heart failure and left bundle branch block (LBBB); however, many patients remain non‐responders. Identifying effective electrical resynchronization early remains an important clinical need. Objective To investigate the association between resolution of V5–V6 R‐wave notching/slurring during left ventricular‐only pacing (LV‐only pacing), combined with an LV‐only pacing percentage ≥ 50% at 1 month, and early left ventricular reverse remodeling in patients with complete LBBB (CLBBB) undergoing CRT. Methods We retrospectively studied 49 patients with CLBBB who underwent CRT. Patients with resolution of V5–V6 R‐wave notching/slurring during LV‐only pacing at implantation and an LV‐only pacing percentage ≥ 50% at 1 month were classified as the R‐Notch Resolution group; all others were classified as the Non–R‐Notch Resolution group. The primary endpoint was left ventricular reverse remodeling at 1 month, defined as a ≥ 15% reduction in left ventricular end‐systolic volume (LVESV) from baseline. Logistic regression analysis was performed to identify associated factors. Results Fifteen patients were classified into the R‐Notch Resolution group and 34 into the Non–R‐Notch Resolution group. One‐month left ventricular reverse remodeling occurred more frequently in the R‐Notch Resolution group (80.0% vs. 47.1%). In multivariable logistic regression analysis, R‐Notch Resolution group status remained independently associated with 1‐month left ventricular reverse remodeling. Conclusion Resolution of V5–V6 R‐wave notching/slurring during LV‐only pacing, combined with an LV‐only pacing percentage ≥ 50% at 1 month, was independently associated with early left ventricular reverse remodeling after CRT.
ABSTRACT Background With over 60 million cases worldwide, atrial fibrillation (AF) is one of the most common cardiac arrhythmias in adults. Pulsed‐field ablation (PFA) has emerged as a significant alternative to thermal ablation for pulmonary vein isolation (PVI). This systematic review and meta‐analysis investigated the efficacy and safety of PFA versus thermal ablation in patients undergoing first‐time PVI. Methods We systematically searched PubMed, Scopus, Web of Science, and Cochrane Library from inception to 2025. Hazard ratios (HRs) with 95% confidence intervals (CIs) were derived from reconstructed Kaplan–Meier survival curves to compare atrial tachyarrhythmia recurrence between PFA and thermal ablation. Random‐effects models were used to compare AF recurrence, durable PVI, redo procedures, phrenic nerve palsy (PNP), and other safety outcomes between the two groups. Results A total of 27 studies comprising 8546 patients were included. Kaplan–Meier reconstruction from ten studies demonstrated higher 12‐month arrhythmia‐free survival with PFA compared with thermal ablation (78.4% [95% CI, 76.1–80.8] vs. 73.4% [95% CI, 71.5–75.4]). Thermal ablation was associated with a significantly higher risk of atrial tachyarrhythmia recurrence (HR 1.28, 95% CI 1.10–1.48; p = 0.001). Subgroup analyses demonstrated that PFA significantly reduced the recurrence risk in patients with paroxysmal AF (HR 1.63, 95% CI 1.31–2.03; p < 0.001), whereas no significant difference was observed in those with persistent AF (HR 1.13, 95% CI 0.92–1.41; p = 0.25). Conclusions PFA was associated with lower rates of atrial tachyarrhythmia and AF recurrence rates than thermal ablation in patients undergoing first‐time PVI; however, these findings should be interpreted cautiously, given the predominance of observational studies.
Background:Therapeutic options for symptomatic non-obstructive hypertrophic cardiomyopathy (nHCM) remain limited. We investigated whether right ventricular apical (RVA) pacing with optimal atrioventricular delay (AVD) can improve myocardial oxygen supply-demand mismatch, assessed using coronary sinus (CS) lactate as a marker of microvascular ischemia. Methods:Patients underwent atrial pacing at 70% of target heart rate followed by AV sequential pacing at individually optimized AVD. CS lactate levels were measured at baseline, during atrial pacing, after washout, and during AV sequential pacing. Results:Baseline CS lactate was 0.55 ± 0.15 mmol/L and increased to 1.13 ± 0.29 mmol/L during atrial pacing. After washout, levels returned to near baseline (0.59 ± 0.21 mmol/L). During AV sequential pacing at optimal AVD (142.8 ± 20.6 ms), CS lactate decreased to 0.86 ± 0.31 mmol/L, showing a significant reduction compared to atrial pacing (p = 0.026). In 15 of 18 patients, CS lactate decreased during AV pacing compared with atrial pacing. Conclusions:AV sequential pacing at optimized AVD reduces CS lactate during exertion in most patients with nHCM, suggesting improved myocardial oxygen balance and reduced microvascular ischemia.
ABSTRACT Background Artificial intelligence‐enabled electrocardiography (AI‐ECG) has emerged as a promising tool for identifying patients with atrial fibrillation (AF) using sinus‐rhythm ECGs. However, some patients with paroxysmal AF (PAF) may be assigned by AI‐ECG to lower AF likelihood categories. Clinical and echocardiographic characteristics associated with AF likelihood assignment by AI‐ECG remain unclear. Methods This single‐center prospective study enrolled adults with documented PAF admitted for catheter ablation who were in sinus rhythm on the admission ECG. The four AF likelihood categories output by AI‐ECG were dichotomized into higher and lower groups for analysis. Logistic regression was used to assess factors associated with assignment by AI‐ECG to the higher AF likelihood group. Results Among 104 patients, 36 were categorized into the lower and 68 into the higher AF likelihood group. Hypertension was associated with lower odds of higher‐group assignment (odds ratio [OR], 0.25; 95% confidence interval [CI], 0.10–0.66). In the echocardiographic model, higher left ventricular mass index (LVMI) was associated with lower (OR, 0.72 per 10 g/m 2 increase; 95% CI, 0.57–0.90) and mild or greater tricuspid regurgitation (TR) with higher (OR, 2.99; 95% CI, 1.14–7.87) odds of higher‐group assignment. Conclusions A lower AF likelihood assignment by AI‐ECG was not uncommon among patients with documented PAF. Hypertension and higher LVMI were inversely associated with assignment to the higher AF likelihood group, whereas mild or greater TR showed a possible positive association. These findings suggest that AI‐ECG‐based AF likelihood assignment varies among patients with documented PAF during sinus rhythm.
High-density electroanatomical mapping during orthodromic tachycardia with alternating short- and long-VA conduction patterns demonstrated an identical earliest atrial breakthrough. Although this supports a common atrial insertion, it cannot distinguish functional longitudinal dissociation within a single accessory pathway from closely adjacent ventricular pathway components converging into a common atrial insertion.
ABSTRACT The Japanese Catheter Ablation (J‐AB) registry, started in August 2017, is a voluntary, nationwide, multicenter, prospective, observational registry performed by the Japanese Heart Rhythm Society (JHRS) in collaboration with the National Cerebral and Cardiovascular Center. From January 2022, the data registration system was changed from Research Electronic Data Capture (REDCap) system to Fountayn system. The purpose of this registry is to collect the details of target arrhythmias, the ablation procedures, including the types of target arrhythmias, outcomes, and acute complications in the real‐world settings. During the year 2024, we have collected a total of 112 151 procedures (mean age of 67.5 years and 65.2% male) from 589 participant hospitals. Detailed data were shown in Figures and Tables.
ABSTRACT Background Electrical storm (ES) is a life‐threatening manifestation of ventricular tachycardia (VT) associated with highmorbidity and mortality. Catheter ablation is an established therapy for VT, but the impact of ES on ablation outcomes remains uncertain. Methods We conducted a systematic review and meta‐analysis in accordance with PRISMA 2020 to compare VT ablation outcomes in patients with and without ES. PubMed, Cochrane Library, and ScienceDirect were searched from inception through January 2026. Eligible studies were comparative cohorts reporting periprocedural or long‐term outcomes. Random‐effects models were used to pool odds ratios (ORs), hazard ratios (HRs), and mean differences (MDs), with heterogeneity assessed using the I 2 statistic. Results Six observational cohort studies including 3531 patients (1183 with ES and 2348 without ES) were included. Acute procedural endpoints, including post‐ablation VT non‐inducibility and residual inducible VT, were similar between groups. Periprocedural or in‐hospital mortality was significantly higher in the ES group (OR 4.71, 95% CI 2.76–8.06), whereas complication rates, procedural duration, radiofrequency ablation time, and need for hemodynamic support did not differ significantly. During follow‐up, ES was associated with higher all‐cause mortality (OR 1.67, 95% CI 1.19–2.35) and greater VT recurrence in both arm‐based (OR 1.45, 95% CI 1.11–1.91) and time‐to‐event analyses (HR 1.35, 95% CI 1.16–1.57). Conclusions VT ablation showed comparable acute procedural success and procedural safety in patients with and without ES. However, ES was associated with higher early and long‐term mortality and greater VT recurrence, supporting its role as a marker of adverse prognosis.
ABSTRACT Background Diabetes mellitus (DM) increases the risk of atrial fibrillation (AF), but the molecular mechanisms underlying DM‐related atrial remodeling remain unclear. This study aimed to characterize transcriptomic differences, including microRNA (miRNA) profiles, between atrial tissue from AF patients with and without DM. Methods Right atrial appendage samples were collected from 12 patients with AF undergoing cardiac surgery (six with DM and six without DM). Total RNA was analyzed by high‐throughput RNA sequencing. Differentially expressed genes (DEGs) and miRNAs were identified using Welch's t ‐test ( p < 0.05), and pathway analyses were performed using Gene Ontology (GO) and Gene Set Enrichment Analysis (GSEA). Results Forty‐six protein‐coding genes and nine miRNAs were differentially expressed between the two groups. Upregulated genes in the DM group, including MYH6 and SLN , were related to contractile and calcium‐handling functions, while downregulated genes, such as ADAMTS4 , CP , and histone family members, were linked to extracellular matrix and chromatin regulation. GO and GSEA analyses revealed activation of mitochondrial ATP synthesis pathways and suppression of immune and inflammatory signaling. Additionally, distinct miRNA expression changes—such as upregulation of miR‐3120 and downregulation of miR‐4524B and miR‐6503 —suggested potential epigenetic regulation mechanisms. Conclusions Transcriptomic profiling revealed that AF with DM is characterized by enhanced mitochondrial metabolism, suppressed immune pathways, and altered miRNA expression. These findings suggest that DM modifies the atrial substrate through metabolic and epigenetic mechanisms, providing novel insights into AF pathogenesis in diabetic patients.
Fixed-tilt biphasic shocks may become ineffective in high-impedance states because phase-2 over-prolongation disrupts optimal charge neutralization. Waveform tuning based on membrane time constants, as implemented by DeFT Response, shortens phase durations to physiologic ranges and lowers the defibrillation threshold. This mechanism-based strategy may enhance the reliability of ICD therapy in patients with rising impedance or high DFTs.
ABSTRACT Cardiac neuromodulation includes various methods, such as vagus nerve stimulation, baroreflex activation therapy, renal denervation, and stellate ganglion intervention, and targets the autonomic imbalance contributing to the pathophysiology of many cardiovascular diseases. Despite promising mechanistic evidence, several landmark trials, including INOVATE‐HF, NECTAR‐HF, and SYMPLICITY HTN‐3, did not meet their primary clinical outcomes, with substantial numbers of non‐responders observed across therapies. Variation in patient response is attributed to several unresolved issues, including insufficient stimulation dosing, off‐target or non‐selective fiber activation, and differences in autonomic phenotypes between patients. Both problems highlight the need for individualized approaches to patient selection, therapy delivery, and monitoring. Artificial intelligence (AI) offers tools to address these problems. In this narrative review, we describe seven families of AI techniques relevant to cardiac neuromodulation: supervised machine learning, deep learning, representation learning, reinforcement learning, multimodal fusion, digital twins with physics‐informed AI, and explainable AI with federated learning. For each family, we summarize how the method works, the cardiac neuromodulation problem it addresses, and the available evidence in the field of cardiac electrophysiology. We then map these techniques to the three core problems of patient selection, real‐time stimulation control, and longitudinal response monitoring. The strongest evidence to date supports representation learning for VNS responder identification, reinforcement learning for closed‐loop VNS control, and digital twins for in silico testing of stimulation protocols. The opportunity for the field is to translate these methods, most of which were developed in adjacent fields, into prospective cardiac neuromodulation trials.
